Analysis device provided with flow sensor, and flow sensor adjustment method

ABSTRACT

The present invention relates to a method of adjusting a flow rate sensor  52  for measuring a travel time of a sample passing through a resistive body. The flow rate sensor  52  includes a straight tube  56 , and plural photo sensors  52 A to  52 E for detecting interfaces  82 A,  82 B between a gas  80  and a liquid  81  traveling in the straight tube  56 . Respective positions of the plural photo sensors  52 A to  52 E are adjusted by detecting the interfaces  82 A,  82 B by using such photo sensors  52 A to  52 E.

TECHNICAL FIELD

The present invention relates to a technology for analyzing a flowproperty or the like of a sample like a blood sample.

BACKGROUND ART

An example scheme of inspecting a flowability of a blood and a conditionof a cell in the blood is a scheme of using a blood filter (see, forexample, patent literatures 1 and 2). The blood filter includes asubstrate formed with minute grooves and another substrate is joinedwith that substrate. When such a blood filter is used, a condition of acell in a blood when the blood passes through the grooves can beobserved.

FIG. 25 is a piping diagram showing an illustrative blood inspectingapparatus using the blood filter. A blood inspecting apparatus 9includes a liquid feeding mechanism 91, a liquid discharging mechanism92, a blood supply mechanism 93 and a flow speed measuring mechanism 94.

The liquid feeding mechanism 91 is for supplying a predetermined liquidto a blood filter 90, and includes liquid reserving bottles 91A, 91B anda liquid feeding nozzle 91C. The liquid reserving bottle 91A reserves anisotonic sodium chloride solution for measuring a flow speed of a blood.The liquid reserving bottle 91B is for reserving a distilled water usedfor rinsing pipings. According to this liquid feeding mechanism 91, as athree-way valve 91D is switched accordingly with the liquid feedingnozzle 91C being attached to the liquid filter 90, a state in which theisotonic sodium chloride solution is supplied to the liquid feedingnozzle 91C and a state in which the distilled water is supplied to theliquid feeding nozzle 91C can be selected.

The liquid discharging mechanism 92 is for discharging a liquid in theblood filter 90, and includes a liquid discharging nozzle 92A, apressure-reduction bottle 92B, a pressure-reduction pump 92C and aliquid discharging bottle 92D. According to this liquid dischargingmechanism 92, as the pressure-reduction pump 92C is actuated with theliquid discharging nozzle 92A being attached to the blood filter 90, aliquid in a piping 92E or the like is discharged in thepressure-reduction bottle 92B. The liquid in the pressure-reductionbottle 92B is discharged in the liquid discharging bottle 92D through apiping 92F by the pressure-reduction pump 92B.

The blood supply mechanism 93 suctions a liquid from the blood filter 90to form a space for retaining a blood, supplies the blood in the spacefor retaining the blood, and includes a sampling nozzle 93A.

The flow speed measuring mechanism 94 is for obtaining informationnecessary for measuring a velocity of a blood traveling through theblood filter 90, and includes a U-tube 94A and a measuring nozzle 94B.The U-tube 94A is arranged at a position higher than that of the bloodfilter 90, and can cause the blood in the blood filter 90 to travel by awater head difference.

According to the blood inspecting apparatus 9, a traveling velocity of ablood is measured as follows.

First, as shown in FIG. 26, the interior of the blood filter 90 isreplaced with an isotonic sodium chloride solution. More specifically,the liquid feeding nozzle 91C of the liquid feeding mechanism 91 isattached to the blood filter 90, and the three-way valve 91D is switchedso that an isotonic sodium chloride solution in the liquid reservingbottle 91A can be supplied to the liquid feeding nozzle 91C. Meanwhile,the liquid discharging nozzle 92A of the liquid discharging mechanism 92is attached to the blood filter 90, and the pressure-reduction pump 92Cis actuated. Accordingly, the isotonic sodium chloride solution in theliquid reserving bottle 91A is supplied to the blood filter 90 throughthe liquid feeding nozzle 91C, and the isotonic sodium chloride solutionpassed through the blood filter 90 is discharged in the liquiddischarging bottle 92D through the liquid discharging nozzle 92A.

Next, the liquid feeding nozzle 91C is detached from the blood filter90, and as shown in FIG. 27A, some of the isotonic sodium chloridesolution in the blood filter 90 are suctioned by the sampling nozzle 93Aof the blood supply mechanism 93, and as shown in FIG. 27B, a space 95for retaining a blood is formed.

Furthermore, as shown in FIG. 28A, a blood is collected from a bloodcollecting tube 96 by the sampling nozzle 93A, and as shown in FIG. 28B,a collected blood 97 is filled in the space 95 of the blood filter 90.

Subsequently, as shown in FIG. 29A, the measuring nozzle 94B of the flowspeed measuring mechanism 94 is attached to the blood filter 90.Accordingly, by a water head difference caused between the U-tube 94Aand the blood filter 90, the liquid in U-tube 94A travels toward theblood filter 90, and a liquid-level position in the U-tube 94A changes.According to the blood inspecting apparatus 9, as shown in FIG. 29B, achange speed of the liquid-level position in the U-tube 94A is detectedby plural photo sensors 98, and based on the detection result, a travelspeed of the blood is calculated.

As shown in FIG. 25, the flowability of the blood in the blood filter 90can be observed on a monitor 99B as an imaging device 99A picks up animage of the blood filter 90.

According to the scheme of utilizing a water head difference between theU-tube 94A and the blood filter 90, however, a liquid-level position inthe U-tube 94A changes, so that a measuring pressure (a pressure actingon a blood 97 in the blood filter 90) varies. Moreover, in order tocause the blood 97 to travel in the blood filter 90 by a water headdifference, it is necessary that pipings 92E, 94C from the U-tube 94A tothe pressure-reduction bottle 92D must be filled with a liquid. Hence,according to the blood inspecting apparatus 9, because a relatively longpiping length is requisite, the piping resistance becomes large.Moreover, in addition to the liquid feeding nozzle 91C and the liquiddischarging nozzle 92A, the measuring nozzle 94B for supplying a liquidfrom the U-tube 94A to the blood filter 90 is requisite, the number ofnozzles for a measurement is large. Furthermore, because the number ofnozzles is large, the pipings become complex, and the number of partslike the number of valves for switching the nozzles 91C, 92A, 93A, and94B is also large, which interrupts miniaturization of the apparatus.The larger the number of parts becomes, the more a part with arelatively high failure rate like a valve is included, so that amean-time-between-failure that is an index of representing a failurerate (a performance) of the apparatus becomes short.

In order to overcome such a problem, a straight tube arrangedhorizontally may be used instead of the U-tube 94A to maintain the waterhead difference at constant. In this case, however, because an effect toa measured value of a flow speed due to the inconsistency in theinternal diameter of the straight tube per product becomes large, it isexpected that the flow speed of a blood passing through the blood filter90 cannot be figured out appropriately. In particular, when the internaldiameter of the straight tube is set to be small in order to increasethe travel speed of the fluid in the straight tube, the effect to theflow speed due to the inconsistency of the internal diameter becomesfurther large. Such inconsistency of the flow speed may cause varying ina measurement precision apparatus by apparatus.

-   Patent Literature 1: Unexamined Japanese Patent Application KOKAI    Publication No. H02-130471-   Patent Literature 2: Unexamined Japanese Patent Application KOKAI    Publication No. H11-118819

DISCLOSURE OF INVENTION Problem to be Solved by Invention

It is an object of the present invention to reduce the number of partsin an analysis apparatus using a resistive body like a blood filterthereby to accomplish miniaturization of the apparatus, to accomplishcost down and extension of a mean-time-between-failure, and to suppressany varying in a measurement precision apparatus by apparatus.

Means for Solving the Problem

According to a first aspect of the present invention, there is providedan analysis apparatus that includes a flow rate sensor for measuring atravel time of a sample (e.g., a blood) passing through a resistivebody. The flow rate sensor includes: a tubular member with a straightpart running straightly; and at least one sensor for detecting aninterface between a first fluid and a second fluid both traveling in thestraight part. The straight part is inclined relative to a horizontaldirection. The straight part may be configured to have an inclined angleadjustable relative to the horizontal direction.

It is preferable that at least one sensor should have a positionadjustable relative to a direction in which the straight part runs.

The analysis apparatus of the present invention further includes, forexample, a piping connected to the downstream side of the tubularmember. In this case, it is preferable that the piping should have alarger internal volume than the volume of the second fluid traveling inthe tubular member.

According to a second aspect of the present invention, there is provideda flow rate sensor adjustment method in the analysis apparatus of thefirst aspect of the present invention. According to this adjustmentmethod, a position of the sensor is adjusted by detecting the interfaceby using the sensor.

According to the flow rate sensor adjustment method of the presentinvention, it is preferable that the interface should be caused totravel by what corresponds to a predetermined amount of the first fluidand a position of the sensor should be adjusted with respect to thetraveled interface.

According to the flow rate sensor adjustment method of the presentinvention, when at least one sensor includes a plurality of sensors, asensor located at a most upstream side among the plurality of sensors isaligned with respect to the interface, the interface is repeatedlycaused to travel by what corresponds to a predetermined amount of thefirst fluid, and positions of the sensors other than the sensor locatedat the most upstream side in the plurality of sensors are adjusted everytime the interface is caused to travel.

It is preferable that the inclined angle of the straight tube should beadjusted after a position of the sensor is adjusted. The inclined angleis set in accordance with, for example, a water head difference actingon the straight part.

In the adjustment method of the present invention, typically, the firstfluid is a liquid and the second fluid is a gas.

The resistive body is one that gives a travel resistance when, forexample, a blood sample travels.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a piping diagram showing a blood inspecting apparatus as anillustrative analysis apparatus according to the present invention;

FIG. 2 is an overall perspective view for explaining a blood filter usedin the blood inspecting apparatus shown in FIG. 1;

FIG. 3 is a cross-sectional view along a line in FIG. 2;

FIG. 4 is an exploded perspective view of the blood filter shown in FIG.2;

FIG. 5 is an exploded perspective view showing the blood filter shown inFIG. 2 as viewed from a bottom;

FIG. 6 is an overall perspective view showing a fluid-channel substratein the blood filter shown in FIG. 2;

FIGS. 7A to 7C are cross-sectional views showing a major part forexplaining the blood filter shown in FIG. 2;

FIG. 8A is a cross-sectional view showing a major part of a crosssection along a communicating groove in the fluid-channel substrateshown in FIG. 6, and FIG. 8B is a cross-sectional view showing a majorpart of a cross section along the straight part of a bank in thefluid-channel substrate shown in FIG. 6;

FIG. 9 is a enlarged perspective view showing a major part of thefluid-channel substrate shown in FIG. 6;

FIG. 10 is a front view showing a flow rate sensor in the bloodinspecting apparatus shown in FIG. 1;

FIG. 11 is a cross-sectional view showing a major part of the flow ratesensor shown in FIG. 10;

FIGS. 12A to 12C are cross-sectional views showing a major part of theflow rate sensor shown in FIG. 10 enlarged in order to explain how itworks;

FIGS. 13A and 13B are front views for explaining how the flow ratesensor shown in FIG. 10 works;

FIG. 14 is a cross-sectional view showing a major part of apressure-reduction bottle in the blood inspecting apparatus shown inFIG. 1;

FIG. 15 is a block diagram of the blood inspecting apparatus shown inFIG. 1;

FIG. 16 is a piping diagram for explaining a gas/liquid replacementoperation by the blood inspecting apparatus shown in FIG. 1;

FIG. 17 is a piping diagram for explaining an air inletting operation bythe blood inspecting apparatus shown in FIG. 1;

FIGS. 18A to 18C are partial transparent views for explaining the statesaround a three-way valve in the air inletting operation by the bloodinspecting apparatus shown in FIG. 1;

FIG. 19 is a piping diagram for explaining a liquid dischargingoperation for forming a space in the blood filter in the bloodinspecting apparatus shown in FIG. 1;

FIGS. 20A and 20B are cross-sectional views around the blood filter forexplaining the liquid discharging operation;

FIG. 21 is a piping diagram for explaining a blood supply operation tothe blood filter in the blood inspecting apparatus shown in FIG. 1;

FIGS. 22A and 22B are cross-sectional views around the blood filter forexplaining the blood supply operation;

FIG. 23 is a piping diagram for explaining a measuring operation by theblood inspecting apparatus shown in FIG. 1;

FIG. 24 is a piping diagram for explaining a rinsing operation for apiping in the blood inspecting apparatus shown in FIG. 1;

FIG. 25 is a piping diagram showing an example of conventional bloodinspecting apparatus;

FIG. 26 is a piping diagram for explaining a gas/liquid replacementoperation by the blood inspecting apparatus shown in FIG. 25;

FIG. 27A is a piping diagram for explaining a liquid dischargingoperation from a blood filter by the blood inspecting apparatus shown inFIG. 25, and FIG. 27B is a cross-sectional view around the blood filterfor explaining the liquid discharging operation;

FIG. 28A is a piping diagram for explaining a blood supply operation tothe blood filter in the blood inspecting apparatus shown in FIG. 25, andFIG. 28B is a cross-sectional view around the blood filter forexplaining the blood supply operation; and

FIG. 29A is a piping diagram for explaining a measuring operation by theblood inspecting apparatus shown in FIG. 1, and FIG. 29B is a front viewfor explaining a fluid-channel sensor in the measuring operation.

DESCRIPTION FOR REFERENCE NUMERALS

-   -   1 Blood inspecting apparatus (analysis apparatus)    -   2 Blood filter    -   33 Pressurizing pump    -   52 Flow rate sensor    -   53 Pressure-reduction bottle    -   54 Pressure-reduction pump    -   58A to 58E Photosensor (of flow rate sensor)    -   56 Straight tube (of flow rate sensor)    -   77 Piping    -   80 Air    -   81 Blood

BEST MODE FOR CARRYING OUT THE INVENTION

A specific example will be given of a blood inspecting apparatus that isan example of an analysis apparatus of the present invention withreference to the accompanying drawings.

A blood inspecting apparatus 1 shown in FIG. 1 is configured to, using ablood filter 2, measure a flowability of a blood sample like a wholeblood, a transformation form of a red blood cell, an activity of a whiteblood cell, etc. The blood inspecting apparatus 1 includes a liquidsupply mechanism 3, a sampling mechanism 4, a liquid dischargingmechanism 5 and an imaging device 6.

As shown in FIGS. 2 to 5, the blood filter 2 provides a fluid channelwhere a blood travels, and includes a holder 20, a fluid-channelsubstrate 21, a packing 22, a transparent cover 23, and a cap 24.

The holder 20 is for retaining the fluid-channel substrate 21, andenables supply of a liquid to the fluid-channel substrate 21 anddischarging of a liquid from the fluid-channel substrate 21. The holder20 has a pair of small-diameter cylinders 25A, 25B provided in theinteriors of a rectangular tube 26 and a large-diameter cylinder 27. Thepair of small-diameter cylinders 25A, 25B are formed in a cylindricalshape having respective upper openings 25Aa, 25Ba, and respective loweropenings 25Ab, 25Bb, and are integrated together with the rectangulartube 26 and the large-diameter cylinder 27 by fins 25C. Thelarge-diameter cylinder 27 is for fixing the fluid-channel substrate 21,and has a cylindrical recess 27A. The cylindrical recess 27A is a partwhere the packing 22 is fitted, and a pair of cylindrical convexities27Aa are formed in the interior of the recess. Provided between therectangular tube 26 and the large-diameter cylinder 27 is a flange 20A.The flange 20A is used to fix the cap 24 to the holder 20, and is formedin a substantially rectangular shape as viewed from the above.Cylindrical protrusions 20C are provided at respective corners 20B ofthe flange 20A.

As shown in FIGS. 3, 6, 7A and 7B, the fluid-channel substrate 21 givesa travel resistance when a blood travels, functions as a filter, and isfixed to the large-diameter cylinder 27 (cylindrical recess 27A) of theholder 20 via the packing 22. As shown in FIGS. 6 to 9, thefluid-channel substrate 21 is formed of, for example, a silicon in arectangular tabular shape as a whole, and has a bank 28 and pluralcommunicating grooves 29 formed by applying a photolithography techniqueor by performing an etching process on one surface of the tabularsilicon.

The bank 28 is so formed as to serpentine at the center of thefluid-channel substrate 21 in the lengthwise direction. The bank 28 hasplural straight portions 28A running in the lengthwise direction of thefluid-channel substrate 21, and an inlet fluid channel 28B and adischarging fluid channel 28C are defined by those straight portions28A. Through holes 28D, 28E corresponding to respective lower openings25Ab, 25Bb of the small-diameter cylinders 25A, 25B of the holder 20 areformed at both sides of the bank 28 as shown in FIGS. 6, 7A and 7B. Thethrough hole 28D is for inletting a liquid from the small-diametercylinder 25A to the fluid-channel substrate 21, and the through hole 28Eis for discharging a liquid in the fluid-channel substrate 21 to thesmall-diameter cylinder 25B.

On the other hand, the plural communicating grooves 29 are so formed asto extend in the widthwise direction of the bank 28 at the straightportions 28A thereof. That is, the communicating grooves 29 cause theinlet fluid channel 28B to be communicated with the discharging fluidchannel 28C. Where a transformability of a cell like a blood cell or ablood platelet is observed, each communicating groove 29 is set to havea width dimension smaller than the diameter of a cell, and is set to be,for example, 4 to 6 μm. Moreover, a space between adjoiningcommunicating grooves 29 is set to be, for example, 15 to 20 μm.

According to the fluid-channel substrate 21, a liquid introduced throughthe through hole 28D successively travels the inlet fluid channel 28B,the communicating grooves 29, and the discharging fluid channel 28C, andis discharged from the fluid-channel substrate 21 through the throughhole 28E.

As shown in FIGS. 2 to 5, the packing 22 is for retaining thefluid-channel substrate 21 in the large-diameter cylinder 27 of theholder 20 in a liquid-tight manner. The packing 22 is formed in adiscoid shape as a whole, and is fitted into the cylindrical recess 27Aof the large-diameter cylinder 27 of the holder 20. The packing 22 isprovided with a pair of through holes 22A and a rectangular recess 22B.The pair of through holes 22A are portions where respective cylindricalconvexities 27A of the large-diameter cylinder 27 of the holder 20 arefitted. As respective cylindrical convexities 27Aa are fitted in thepair of through holes 22A, the packing 22 is positioned relative to thelarge-diameter cylinder 27. The rectangular recess 22B is for retainingthe fluid-channel substrate 21, and is formed in a shape correspondingto the contour of the fluid-channel substrate 21. However, the depth ofthe rectangular recess 22B is set to be substantially same as themaximum thickness of the fluid-channel substrate 21 or slightly smallerthan that. The rectangular recess 22B is provided with a pair ofcommunicating holes 22C, 22D. Those communicating holes 22C, 22D are forcausing respective lower openings 25Ab, 25Bb of the small-diametercylinders 25A, 25B of the holder 20 to be communicated with the throughholes 28D, 28E of the fluid-channel substrate 21.

As shown in FIGS. 3 to 5, the transparent cover 23 abuts thefluid-channel substrate 21 to cause the inlet fluid channel 28B, thecommunicating grooves 29, and the discharging fluid channel 28C of thefluid-channel substrate 21 to have a closed cross-sectional structure.The transparent cover 23 is formed of, a glass in a discoid shape. Thetransparent cover 23 has a thickness set to be smaller than the depth ofthe cylindrical recess 27A of the large-diameter cylinder 27 of theholder 20, and the total of the maximum thicknesses of the transparentcover 23 and the packing 22 is set to be larger than the depth of thecylindrical recess 27A.

As shown in FIGS. 2 to 5, the cap 24 is for fixing the fluid-channelsubstrate 21 together with the packing 22 and the transparent cover 23,and has a cylinder 24A and a flange 24B. The cylinder 24A overcoats thelarge-diameter cylinder 27 of the holder 20, and has a through hole 24C.The through hole 24C is for ensuring the visibility when a travelcondition of a blood in the fluid-channel substrate 21 is checked. Theflange 24B has a form corresponding to the flange 20A of the holder 20,and has recesses 24E at respective corners 24D. The recess 24E is a partwhere the cylindrical protrusion 20C of the flange 20A of the holder 20is fitted.

As explained above, the transparent cover 23 has a thickness which isset to be smaller than the depth of the cylindrical recess 27A in thelarge-diameter cylinder 27 of the holder 20, and the total of themaximum thicknesses of the transparent cover 23 and the packing 22 isset to be larger than the depth of the cylindrical recess 27A.Conversely, the rectangular recess 22B has a depth set to besubstantially same or slightly larger than the maximum thickness of thefluid-channel substrate 21. Accordingly, when the fluid-channelsubstrate 21 is fixed together with the packing 22 and the transparentcover 23 by the cap 24, the packing 22 is compressed and the transparentcover 23 liquid-tightly contacts the fluid-channel substrate 21appropriately, so that it is possible to suppress any leakage of aliquid between the fluid-channel substrate 21 and the transparent cover23.

The liquid supply mechanism 3 shown in FIG. 1 is for supplying a liquidto the blood filter 2, and includes bottles 30, 31, a three-way valve32, a pressurizing pump 33, and a liquid supply nozzle 34.

The bottles 30, 31 are for reserving respective liquids to be suppliedto the blood filter 2. The bottle 30 reserves an isotonic sodiumchloride solution used for inspection of a blood, and is connected tothe three-way valve 32 by a piping 70. On the other hand, the bottle 31is for retaining a distilled water for rinsing of the piping, and isconnected to the three-way valve 32 by a piping 71.

The three-way valve 32 is for selecting a kind of a liquid to besupplied to the liquid supply nozzle 34, and is connected to thepressurizing pump 33 by a piping 72. That is, by switching the three-wayvalve 32 as needed, either one of the states: a state in which theisotonic sodium chloride solution is supplied to the liquid supplynozzle 34 from the bottle 30; and a state in which the distilled wateris supplied to the liquid supply nozzle 34 from the bottle 31 can beselected.

The pressurizing pump 33 provides power for moving a liquid from thebottles 30, 31 to the liquid supply nozzle 34, and is connected to theliquid supply nozzle 34 by a piping 73. Various kinds of conventionallyknown pumps can be used as the pressurizing pump 33, but from thestandpoint of miniaturization of the apparatus, it is preferable to usea tube pump.

The liquid supply nozzle 34 is for supplying a liquid from each bottle30, 31 to the blood filter 2, and is attached to the upper opening 25Aaof the blood filter 2. The liquid supply nozzle 34 has a joint 35 whichis attached to the upper opening 25Aa (see FIGS. 2 and 3) of thesmall-diameter cylinder 25A in the blood filter 2, and has another endconnected to the pressurizing pump 33 by a piping 73.

The sampling mechanism 4 is for supplying a blood to the blood filter 2,and includes a sampling pump 40, a blood supply nozzle 41, and aliquid-level detecting sensor 42.

The sampling pump 40 is for providing power for suctioning/delivering ablood, and comprises, for example, a syringe pump.

The blood supply nozzle 41 is used with a chip 43 being attached to aleading end thereof, and suctions a blood in the interior of the chip 43from a blood collecting tube 81 as the sampling pump 40 applies anegative pressure to the interior of the chip 43, and delivers the bloodas the sampling pump 40 pressurizes the blood in the chip.

The liquid-level sensor 42 is for detecting the liquid level of theblood suctioned into the interior of the chip 43. When the pressureinside the chip 43 becomes a predetermined value, the liquid-levelsensor 42 outputs a signal to that effect, and detects that a targetamount of blood is suctioned.

The liquid discharging mechanism 5 is for discharging a liquid insideeach piping and the blood filter 2, and includes a liquid dischargingnozzle 50, a three-way valve 51, a flow rate sensor 52, apressure-reduction bottle 53, a pressure-reduction pump 54, and a liquiddischarging bottle 55.

The liquid discharging nozzle 50 is for suctioning a liquid inside theblood filter 2, and is attached to the upper opening 25Ba (see FIGS. 2and 3) of the small-diameter cylinder 25B in the blood filter 2. Theliquid discharging nozzle 50 has a joint 50A which is provided at aleading end thereof and attached to the upper opening 25Ba of the bloodfilter 2, and has another end connected to the three-way valve 51 by apiping 74.

The three-way valve 51 is connected to the flow rate sensor 52 by apiping 76, and a piping 7A to be opened to the atmosphere is connectedthereto. The three-way valve 51 can select a state in which a liquid isdischarged to the pressure-reduction bottle 53 and a state in which airis inlet into a piping 76 through the piping 7A. The three-way valve 51is provided at the upstream side of the flow rate sensor 52, and air isinlet into a straight tube 56 of the flow rate sensor 52 to be discussedlater from the upstream side.

As shown in FIGS. 10 to 12, the flow rate sensor 52 is used in order tocapture interfaces 82A, 82B between an air 80 and a blood 81 to regulatethe inlet amount of air 80, or to measure a travel speed of the blood inthe blood filter 2. The flow rate sensor 52 includes plural (in thefigures, five) photo sensors 52A, 52B, 52C, 52D, and 52E, the straighttube 56, and a plate 57.

The plural photo sensors 52A to 52E are for detecting whether or not theinterfaces 82A, 82B pass through respective areas in the straight tube56, and are arranged side by side in a horizontal direction with anequal clearance in an inclined condition toward the horizontaldirection.

Each photo sensor 52A to 52E comprises a light emitting device 52Aa,52Ba, 52Ca, 52Da, 52Ea and a photo sensitive device 52Ab, 52Bb, 52Cb,52Db, and 52Eb, and the flow rate sensor is configured as a transmissivesensor having those devices 52Aa to 52Ea, 52Ab to 52Eb arranged so as toface with each other.

Needless to say, the photo sensors 52A to 52E are not limited to atransmissive type, but a reflective type can be used.

As shown in FIG. 13A, each photo sensor 52A to 52E is fixed to eachsubstrate 58A, 58B, 58C, 58D, and 58E, and is movable along the straighttube 56 together with each substrate 58A to 58E. The substrates 58A to58E are fixed to the plate 57 by bolts 59C through respective slots58Aa, 58Ba, 58Ca, 58Da, and 58Ea, and can move along respective slots58Aa to 58Ea by loosening respective bolts 58Aa to 58Ea. Accordingly,each photo sensor 52A to 52E can move along the straight tube 56 (eachslot 58Aa to 58Ea) by moving each substrate 58A to 58E with each bolt58Aa to 58Ea being loosen, and can be positioned by tightening each bolt58Aa to 58Ea.

The position of each photo sensor 52A to 52E is adjusted by aligningeach of the plural photo sensors 52A to 52E relative to the interface82B after the upstream-side interface 82B between the air 80 and theliquid 81 is moved by what corresponds to a predetermined amount of theliquid 81.

More specifically, first, with the air 80 being present in the straighttube 56, the photo sensor 52A is aligned with respect to the interface82A between the air 80 and the liquid 81. This alignment is carried outby moving the substrate 58A along the straight tube 56 while a change inan amount of received light by the photo sensitive device 52Ab of thephoto sensor 52A is being checked.

Next, the interface 82A is moved by what corresponds to thepredetermined amount of liquid 81. For example, when the flow ratesensor 52 is to detect by a total of 100 μL of the travelling of theamount of the liquid 81 which corresponds to 25 μL, after the photosensor 52A is aligned, the interface 82A is repeatedly moved by anamount corresponding to 25 μL of the liquid 81, and each photo sensor52B to 52E is aligned with respect to the interface 82A after movement.Respective photo sensors 52B to 52E are aligned by moving respectivesubstrates 58B to 58E along the straight tube 56 while a change in theamount of received light by respective photo sensitive devices 52Bb to52Eb is being checked like the case of the photo sensor 52A.

The movement of the interface 82A in the straight tube 56 (supplying ofa tiny amount (e.g., 25 μL) of the liquid 81) can be appropriatelyaccomplished by using a highly precise pump with the highly precise pumpbeing connected to the straight tube 56 by a piping. The highly precisepump is typically not built in the blood inspecting apparatus 1, but isprepared separately for alignment of the photo sensors 52B to 52E.

Needless to say, adjustment of the position of each photo sensor 52A to52E can be carried out by detecting the interface 82A at the downstreamside, and can be carried out through other schemes. For example,adjustment can be made based on a first travel time that is measured bydetecting the interface 82A between the air 80 and the liquid 81 byusing the plural photo sensors 52A to 52E when a straight tube(reference tube) different from the actually installed straight tube isarranged. More specifically, first, a time and a velocity that air(interface) travels between adjoining photo sensors 52A to 52E when thereference tube is installed are measured beforehand. Next, a time and avelocity that the air 80 (interface 82A) travels between adjoining photosensors 52A to 52E when the straight tube 56 actually built in theapparatus is installed are measured beforehand. Subsequently, when thereis inconsistency (e.g., a difference) in the travel time and thevelocity between the air when the reference tube is installed and theair 80 (interface 82A) when the straight tube actually used isinstalled, the photo sensors 52B to 52E with such inconsistency aremoved together with respective substrates 58A to 58E, and the distanceto the photo sensor 52A is made appropriate. Finally, by tightening allbolts 58Aa to 58Ea, respective positions of the photo sensors 52B to 52Eare settled.

As respective positions of the photo sensors 52B to 52E are adjusted inthis fashion, the plural photo sensors 52B to 52E can be arranged with aclearance corresponding to the predetermined amount of liquid 81.Therefore, even if there is a difference in the internal diameter of thestraight tube 56 actually installed in the apparatus (inconsistency ofthe internal diameter with that of the reference tube), it is possibleto suppress occurrence of a measurement error inherent to suchdifference. In particular, when the internal diameter of the straighttube 56 is set to be small, it is possible to appropriately suppressoccurrence of a measurement error inherent to the difference in theinternal diameter.

As shown in FIGS. 10 and 11, the straight tube 56 is a part where theair 80 travels at the time of a measurement, is connected to thethree-way valve 51 by a piping 76, and is communicated with the interiorof the pressure-reduction bottle 53 through a piping 77 (see FIG. 1). Itis preferable that respective internal diameters of the pipings 76, 77in the vicinity of the straight tube 56 should be same or substantiallysame (e.g., an internal diameter corresponding to −3% to +3% of aninternal area of the straight tube 56) as that of the straight tube 56.The straight tube 56 is fixed to the plate 57 so as to be positionedbetween each light emitting device 52Aa to 52Ea and each photo sensitivedevice 52Ab to 52Eb in each photo sensor 52A to 52E and to be inclinedwith respect to the horizontal direction. The straight tube 56 is formedof a material with a transparency, e.g., a transparent glass or atransparent resin in a cylindrical shape with a uniform cross section. Acylinder with a uniform cross section means a circular cross sectionwith a constant or substantially constant internal diameter (e.g., aninternal diameter corresponding to the internal area within a range from−3% to +3% which is a target internal area). The internal diameter ofthe straight tube 56 can be set to be within a range which enablesmeasurement of a travel speed of the air 80 appropriately, and forexample, is set to be 0.9 mm to 1.35 mm which is a smaller internaldiameter than those of other pipings. Moreover, in consideration of adimensional error in the internal diameter, it is desirable that thestraight tube 56 should be formed of a transparent glass. This enablesmore precise measurement of a travel speed of the air 80.

As shown in FIG. 13B, the plate 57 enables adjustment of the inclinedangle of the straight tube 56, and is fixed by bolts 59B, 59C. With thebolts 59B, 59C being loosened, the plate 57 is rotatable around the bolt59B by relatively moving the bolt 59C along the arcuate slot 57A.Accordingly, the straight tube 56 can adjust the inclined angle to thehorizontal direction by rotating the plate 57 with the bolts 58Aa to58Ea being loosened.

The inclined angle of the plate 57 (straight tube 56) is set inaccordance with a water head difference acting on the straight tube 56.That is, the water head difference acting on the straight tube 56includes an error caused among devices due to a difference in theinternal diameters of various pipings including the straight tube 56used in the apparatus, so that if the inclined angle of the straighttube 56 is adjusted, it is possible to suppress occurrence of ameasurement error inherent to a difference in water head differences.Note that the inclined angle of the straight tube 56 can be set byutilizing a travel speed and a travel time when the interfaces 82A, 82Bare moved in the straight tube 56. In this case,

As shown in FIGS. 12A and 12B, when the air 80 (interfaces 80A, 80B)travels in the straight tube 56, a ratio between the isotonic sodiumchloride solution and the air 80 at an area corresponding to each photosensor 52A to 52E gradually changes, so that the amount of receivedlight (transmittance) obtained by the photo sensitive device 52Ab to52Eb in the photo sensor 52A to 52E changes. Accordingly, the interfaces80A, 80B can be detected based on a time when the amount of receivedlight (transmittance) obtained by the photo sensor 52A to 52E startschanging or on a time when the amount of received light (transmittance)becomes a constant value after the amount of received light(transmittance) starts changing. When passing of the interfaces 80A, 80Bthrough plural photo sensors 52A to 52E is individually detected, a timewhen the interfaces 80A, 80B pass through adjoining photo sensors 52A to52E, i.e., a travel time of the air 80 (interfaces 80A, 80B) can bedetected. Moreover, by providing equal to or larger than three photosensors 52A to 52E, it is possible to measure not only a travel speed ofthe air 80 (interfaces 80A, 80B) at a certain time but also a change inthe travel speed of the air 80 (interfaces 80A, 80B) along withadvancement of the time.

Note that the installation interval of the plural photo sensors 52A to52E is selected based on the amount of blood to be caused to travel theblood filter 2, the internal diameter of the straight tube 56, etc., andis selected from distances corresponding to an amount equal to 10 to 100μL with reference to a fluid volume. For example, when 100 μL of theblood is caused to travel the blood filter 2, the installation intervalof the plural photo sensors 52A to 52E is set to be an amountcorresponding to 25 μL.

The travel speed of the air 80 depends on the travel resistance when theblood travels the fluid-channel substrate 21 in the blood filter 2 (seeFIGS. 1 to 3). Accordingly, by detecting the travel speed of the air 80(interfaces 82A, 82B) by the flow rate sensor 52, it is possible toobtain information like the flowability of the blood.

The pressure-reduction bottle 53 shown in FIG. 1 is for temporarilyreserving a waste liquid, and is for defining a pressure-reductionspace. The pressure-reduction bottle 53 is connected to the flow ratesensor 52 by the piping 77, and is connected to the pressure-reductionpump 54 by a piping 78. The piping 77 has a length set to have a largerinternal volume than the volume of air inlet into the straight tube 56.Accordingly, in detection of traveling of the interfaces 82A, 82B, it ispossible to prevent a blowout of the air 80 into the pressure-reductionbottle 53 while the interfaces 82A, 82B are caused to travel in thestraight tube 56. As a result, in detection of the interfaces 82A, 82B,it is possible to suppress a change in the travel resistance against thefluid, thereby enabling appropriate detection of the travel states ofthe interfaces 82A, 82B.

As shown in FIG. 14, the pressure-reduction bottle 53 has a cap 53A, andis connected to the pipings 77, 78 through the cap 53A. A connected part77A of the piping 77 with the pressure-reduction bottle 53 is arrangedso as to run horizontally or substantially horizontally. A connectedpart 78A further protrudes into the interior of the pressure-reductionbottle 54. The cap 53A has a wall 53B provided so as to face an end faceof the connected part 77A of the piping 77.

In the pressure-reduction bottle 53, because the connected part 77A ofthe piping 77 is arranged horizontally or substantially horizontally, incomparison with a case in which the connected part is arrangedvertically, a water head difference acting on the straight tube 56 canbe easily and surely set to be a target value.

Arrangement of the connected part 77A protruding in the interior of thepressure-reduction bottle 53 suppresses traveling of the liquiddelivered from the connected part 77A along the internal surface of thepressure-reduction bottle 53. That is, when the liquid travels along theinternal surface of the pressure-reduction bottle 53, a water headdifference acting on the straight tube 67 may be shifted from the setvalue, but protrusion of the connected part 77A can prevent the liquidfrom traveling along the internal surface of the pressure-reductionbottle 53.

By providing the wall 53B so as to face the end face of the connectedpart 77A, it is possible to prevent the liquid delivered from theconnected part 77A from being splashed around the cap 53A, and thedelivered liquid can be appropriately guided to the bottom of thepressure-reduction bottle 53. In addition, when the connected part 77Ais arranged horizontally or substantially horizontally, by providing thewall 53B, a negative pressure can appropriately act on the connectedpart 77A.

The pressure-reduction pump 54 shown in FIG. 1 is for reducing thepressure inside the pressure-reduction bottle 53 in order to suction aliquid inside the blood filter 2 or to inlet the atmosphere into thepiping 7A. The pressure-reduction pump 54 is connected to thepressure-reduction bottle 53 by the piping 78, is connected to theliquid discharging bottle 55 via a piping 79, and also has a function offeeding a waste liquid in the pressure-reduction bottle 53 to the liquiddischarging bottle 55. Various kinds of pumps can be used as thepressure-reduction pump 56, but from the standpoint of miniaturizationof the apparatus, it is preferable to use a tube pump.

The liquid discharging bottle 55 is for reserving a waste liquid in thepressure-reduction bottle 53, and is connected to the pressure-reductionbottle 53 by the pipings 78, 79.

The imaging device 6 is for picking up an image of a travel state of ablood in the fluid-channel substrate 21. The imaging device 6 comprises,for example, a CCD camera, and is arranged so as to position ahead ofthe fluid-channel substrate 21. An image pickup result by the imagingdevice 6 is output to, for example, a monitor 60, so that it is possibleto check the travel state of the blood in real time or as a recordedimage.

The blood inspecting apparatus 1 further includes a controller 10 and anoperating unit 11 as shown in FIG. 15 in addition to the individualunits shown in FIG. 1.

The controller 10 is for controlling individual units. The controller 10performs, for example, switching control on the three-way valves 32, 51,driving control on each pump 33, 54, driving control on each nozzle 34,41, and 50, and operation control on the imaging device 6 and themonitor 60.

The operating unit 11 performs arithmetic operation necessary forcausing individual units to operate, and based on a monitoring result bythe flow rate sensor 52, calculates a travel speed (flowability) of theblood in the blood filter 2.

Next, an explanation will be given of an operation of the bloodinspecting apparatus 1.

First, as shown in FIG. 16, with the blood filter 2 being set at apredetermined position, an initiation of starting measurement is given.This initiation is given as a user operates a button of the bloodinspecting apparatus 1 or is automatically given when the user sets theblood filter 2 thereto. When recognizing that the initiation of startingmeasurement is given, the controller 10 (see FIG. 14) performs agas/liquid replacement operation in the interior of the blood filter 2.More specifically, first, the controller 10 (see FIG. 15) attaches theliquid supply nozzle 34 of the liquid supply mechanism 3 to the upperopening 25Aa of the small-diameter cylinder 25A in the blood filter 2,and attaches the liquid discharging nozzle 50 of the liquid dischargingmechanism 5 to the upper opening 25Ba of the small-diameter cylinder 25Bin the blood filter 2. Meanwhile, the controller 10 (see FIG. 15)switches the three-way valve 32 to make the bottle 30 communicated withthe liquid supply nozzle 34, and switches the three-way valve 51 to makethe liquid discharging nozzle 50 communicated with thepressure-reduction bottle 53. That is, the path between the bottle 30and the pressure-reduction bottle 53 is communicated through theinterior of the blood filter 2. In this state, the controller 10 (seeFIG. 14) actuates the pressurizing pump 33 of the liquid supplymechanism 3 and the pressure-reduction pump 54 of the liquid dischargingmechanism 5. The pressure by the pressurizing pump 33 is set to be, forexample, 1 to 150 kPa, and the reduced pressure by thepressure-reduction pump 54 is set to be 0 to −50 kPa.

When the pressurizing pump 33 and the pressure-reduction pump 54 areactuated in this fashion, an isotonic sodium chloride solution in thebottle 30 is supplied to the liquid supply nozzle 34 through the pipings71 to 73, passes through the interior of the blood filter 2, and isdischarged in the pressure-reduction bottle 53 through the liquiddischarging nozzle 50 and the pipings 74 to 77. The isotonic sodiumchloride solution discharged in the pressure-reduction bottle 53 isdischarged in the liquid discharging bottle 55 through the pipings 78,79 by power of the pressure-reduction pump 54. Accordingly, a gas in theinterior of the blood filter 2 is evacuated by the isotonic sodiumchloride solution, and the interior of the blood filter 2 is replacedwith the isotonic sodium chloride solution.

According to the blood inspecting apparatus 1, the gas/liquidreplacement for the blood filter 2 is carried out by using thepressurizing pump 33 arranged at the upstream side of the blood filter 2and the pressure-reduction pump 54 arranged at the downstream side ofthe blood filter 2. Accordingly, in comparison with a case in which onlythe pressure-reduction pump 54 arranged at the downstream side of theblood filter 2 is used, a possibility that air bubbles remain in theinterior of the blood filter 2 is remarkably reduced, and a timenecessary for evacuating the gas in the interior of the blood filter 2can be also reduced. This enables reduction of a time necessary for ablood inspection. Moreover, according to the blood inspecting apparatus1, although the pressurizing pump 33 is also used together with thepressure-reduction pump 54, pump power necessary for a gas/liquidreplacement is reduced and a replacement time can be shortened, therebyreducing the running cost.

Next, in the blood inspecting apparatus 1, as shown in FIG. 17, aprocess of inletting air into the interior of the piping 76 is executed.More specifically, the controller 10 (see FIG. 15) stops actuating thepressure-reduction pump 54, switches the three-way valve 51 into a stateshown in FIG. 18B from a state shown in FIG. 18A to make the piping 76communicated with the atmosphere through the piping 7A. At this time,the pressure-reduction bottle 53 (see FIG. 16) is in apressure-reduction state by the former gas/liquid replacement.Accordingly, by making the piping 76 communicated with the atmospherethrough the piping 7A, because of the negative pressure by thepressure-reduction bottle 53 (see FIG. 17), as shown in FIGS. 18B and18C, the air 80 is inlet into the piping 76 through the piping 7A.Inletting of the air 80 into the piping 76 is being carried out untilthe target amount of air 80 is inlet into the piping 76. The amount ofair 80 to be inlet into the piping 76 is, for example, roughly same(e.g., 100 μL) as the blood to be supplied to the blood filter 2.Inletting of the air into the piping 76 is terminated by switching thethree-way valve 51 when, for example, the photo sensor 52A to 52Eselected beforehand detects a downstream-side interface between the air80 and the liquid (isotonic sodium chloride solution) 81. At this time,the air 80 is present as residual air in the halfway of the liquid(isotonic sodium chloride solution) 81. That is, the liquid (isotonicsodium chloride solution) 81 is present at both upstream side anddownstream side of the air 80.

Needless to say, how to terminate inletting of the air into the piping76 is not limited to the scheme of detecting the downstream-sideinterface by the photo sensor 52A, and for example, it may be controlledbased on an open time of the three-way valve 51 to the atmosphere.

Next, as shown in FIG. 19, in the blood inspecting apparatus 1, apredetermined amount of isotonic sodium chloride solution 81 isdischarged from the blood filter 2 to ensure a space 83 for retaining ablood to the blood filter 2. More specifically, the controller 10 (seeFIG. 15) detaches the liquid supply nozzle 34 from the blood filter 2,and actuates the pressure-reduction pump 54. Accordingly, as shown inFIGS. 20A and 20B, the isotonic sodium chloride solution in the interiorof the blood filter 2 is suctioned and eliminated through the liquiddischarging nozzle 50, and an air 84 is inlet into the blood filter 2.At this time, as shown in FIGS. 21A and 21B, the isotonic sodiumchloride solution 81 in the pipings 76, 77 travels toward thepressure-reduction bottle 53 (see FIG. 19), and together with thistravelling, the air 80 in the piping 76 also travels toward thepressure-reduction bottle 53 (see FIG. 19).

Meanwhile, the photo sensors 52A to 52E of the flow rate sensor 52detect a travel distance of the air 80 (interface 80A at the downstreamside). In the photo sensors 52A to 52E, when the air 80 passes through,the amount of received light by the photo sensitive devices 52Ab to 52Ebis large, and when the liquid 81 passes through, the amount of receivedlight by the photo sensitive devices 52Ab to 52Eb is small, so that bymonitoring a change in the amount of received light by the photosensitive devices 52Ab to 52Eb, the photo sensors 52A to 52E can detectthe air 80 (interface at the downstream side). Thereafter, when thephoto sensors 52A to 52E detect that the air 80 travels by apredetermined distance, the controller 10 (see FIG. 15) causes theisotonic sodium chloride solution and the air 80 to stop travelling.

Inletting of the air 80 through the piping 7A (see FIGS. 18A to 18C) canbe terminated when, for example, the photo sensor 52A detects theinterface 80A at the downstream side. Conversely, in a case in which theamount of inlet air 80 through the piping 7A is set to be roughly sameas the amount of inlet blood to the blood filter 2, when the photosensor 52A detects the interface 82A at the downstream side, theinterface 82A at the upstream side can correspond to a positiondetectable by the photo sensor 82B.

As explained above, according to the blood inspecting apparatus 1, bydetecting the position of the air 80 at the flow rate sensor 52, theamount of discharged isotonic sodium chloride solution from the bloodfilter 2 is regulated. Accordingly, in comparison with a case in whichthe amount of discharged isotonic sodium chloride solution is regulatedby the liquid-level detecting sensor at the blood supply nozzle like thecase of the conventional blood inspecting apparatus, it is possible forthe blood inspecting apparatus 1 to regulate the amount of dischargedisotonic sodium chloride solution (accomplishment of a proper interfaceposition) within a short time. Therefore, it becomes possible to shortena time necessary for a blood inspection.

Next, as shown in FIG. 21, the controller 10 (see FIG. 15) supplies ablood 84 to the space 83 provided in the blood filter 2. Morespecifically, the controller 10 (see FIG. 15) suctions a blood from theblood collecting tube 85 into the interior of the chip 43 attached tothe blood supply nozzle 41 by utilizing power by the sampling pump 40,and delivers the blood 84 in the chip 43 to the space 82 in the bloodfilter 2 as shown in FIGS. 22A and 22B. The delivery amount of blood 84with respect to the blood filter 2 is set to be an amount correspondingto the volume of the space 83, and the delivery amount is controlled bycausing the liquid-level detecting sensor 42 (see FIG. 22) to detect theliquid level of the blood in the interior of the chip 43.

Next, according to the blood inspecting apparatus 1, as shown in FIG.23, the blood 84 supplied to the space 82 in the blood filter 2 isinspected. More specifically, the controller 10 (see FIG. 14) dischargesthe isotonic sodium chloride solution 81 in the blood filter 2 throughthe liquid discharging nozzle 50 by utilizing power by thepressure-reduction pump 54. In the meantime, in the blood filter 2, theblood 84 is moved together with the isotonic sodium chloride solution84.

More specifically, in the blood filter 2, the blood 84 passes through afluid channel (see FIGS. 6 to 9) formed between the fluid-channelsubstrate 21 and the transparent cover 23, and is moved to thesmall-diameter cylinder 25B. In the fluid-channel substrate 21, as isexplained with reference to FIGS. 6 to 9, the blood 84 is inlet into theinlet fluid channel 28B through the through hole 28D, successivelytravels the communicating grooves 29 and the discharging fluid channel28C, and is discharged through the through hole 28E. When the widthdimension of the communicating groove 29 is set to be smaller than thediameter of a cell like a blood cell or a blood platelet in the blood84, the cell travels the communicating groove 29 wile deforming, orcauses the communicating groove 29 to be clogged. Such a condition ofthe cell is subjected to an image pickup by the imaging device 6. Animage pickup result by the imaging device 6 may be displayed on themonitor 60 in real time or may be displayed on the monitor 60 afterrecorded.

Meanwhile, as shown in FIGS. 11 and 12, the flow rate sensor 52 monitorstraveling of the interface 82B at the upstream side which travels thestraight tube 56. The operating unit 11 (see FIG. 15) determines whetheror not the air 80 passes through based on information obtained from eachphoto sensor 52A to 52E and calculates the travel speed of the air 80.The travel speed of the air 80 relates to the travel speed of the blood84, i.e., the flowability (resistance) of the blood 84, so that thecondition of the blood 84 can be figured out from the travel speed ofthe air 80.

Because the flow rate sensor 52 employs a structure that the straighttube 56 is inclined relative to the horizontal direction, an effect by adifference in the internal diameter of the straight tube 56 product byproduct affecting a measured value of a flow speed like a case in whichthe straight tube 56 is arranged along the horizontal direction issuppressed. Therefore, according to the inclined straight tube 56, it ispossible to appropriately figure out the flow speed of the blood 83passing through the blood filter 2. In particular, under a condition inwhich an effect by a difference in the internal diameter affecting theflow speed is large like a case in which the internal diameter of thestraight tube 56 is set to be small so as to increase the travel speedof the air 80 in the straight tube 56, it is possible to suppressvarying of the measurement precision apparatus by apparatus.

Moreover, in the blood filter 2, when the blood is caused to travel, theisotonic sodium chloride solution 81 is present at the upstream side ofthe air 80. On the other hand, because the piping 77 connected to thestraight tube 56 has a length set to have a larger internal volume thanthe volume of the air 81 caused to travel the straight tube 56, theisotonic sodium chloride solution 81 is always present at the downstreamside of the air 80 while the air 80 is caused to travel in the straighttube 56. Accordingly, it is possible to suppress a change in a travelresistance due to traveling of the air 80 in the piping while the bloodis caused to travel. As a result, a linearity in a relationship betweenthe travel speed of the blood 83 and the travel time thereof can besufficiently secured, thereby making it possible to measure the travelspeed of the blood 83 precisely.

In particular, if a dimension of a part where the air 80 passes through,e.g., the internal diameter of the straight tube 56 is set to be uniform(constant or substantially constant), or in addition to the straighttube 56, if respective internal diameters of the pipings 76, 77connected to the straight tube 56 in the vicinity of the straight tube56 are set to be same or substantially same (e.g., within a range wherea different in the internal diameters with respect to the straight tubeis from −3% to +3%) as that of the straight tube 56, even if the air 80travels back and forth of the straight tube 56, it is possible tosuppress a change in a contact area between the air 80 and the internalsurface of the piping, thereby maintaining the contact area at constantor substantially constant.

As shown in FIG. 24, when inspection of the blood completes, based on aselection given by the user, the pipings 73, 74, 76, and 77 of theliquid discharging mechanism 5 are rinsed. This rinsing process iscarried out as the user selects a rinsing mode with a dummy chip 2′ forrinsing being set at the position where the blood filter 2 is set. Thedummy chip 2′ has the same external shape as that of the blood filter 2,and has a communicating hole 20′ provided therein. The communicatinghole 20′ has openings 21′, 22′ provided at respective portionscorresponding to the upper openings 25Aa, 25Ba of the small-diametercylinders 25A, 25B (see FIGS. 2 and 3) in the blood filter 2.

In the blood inspecting apparatus 1, when the rinsing mode is selected,the controller 10 (see FIG. 14) first attaches the liquid supply nozzle34 of the liquid supply mechanism 3 to the opening 21′ of thecommunicating hole 20′ of the dummy chip 2′, and attaches the liquiddischarging nozzle 50 of the liquid discharging mechanism 5 to theopening 22′ of the communicating hole 20′ of the dummy chip 2′.Meanwhile, the controller 10 (see FIG. 14) switches the three-way valve32 to make the bottle 31 communicated with the liquid supply nozzle 34,and switches the three-way valve 51 to make the liquid dischargingnozzle 50 communicated with the pressure-reduction bottle 53. That is, apath between the bottle 31 and the pressure-reduction bottle 53 iscommunicated through the communicating hole 20′ of the dummy chip 2′. Inthis state, the controller 10 (see FIG. 15) actuates the pressurizingpump 33 of the liquid supply mechanism 3 and the pressure-reduction pump54 of the liquid discharging mechanism 5. The pressure by thepressurizing pump 33 is set to be, for example, 1 to 150 kPa, and thereduced pressure by the pressure-reduction pump 54 is set to be 0 to −50kPa.

When the pressurizing pump 33 and the pressure-reduction pump 54 areactuated in this fashion, the distilled water in the liquid bottle 31 issupplied to the liquid supply nozzle 34 through the pipings 70, 72, and73, passes through the communicating hole 20′ of the dummy chip 2′, andis discharged in the pressure-reduction bottle 53 through the liquiddischarging nozzle 50 and the pipings 73, 74, 76, and 77. The distilledwater discharged in the pressure-reduction bottle 53 is discharged inthe liquid discharging bottle 55 through the pipings 78, 79 by power ofthe pressure-reduction pump 54. Accordingly, the pipings 73, 74, 76, and77 in the liquid discharging mechanism 5 are rinsed by the distilledwater.

According to the blood inspecting apparatus 1, the condition of theblood is figured out based on information from the flow rate sensor 52provided at the downstream side of the blood filter 2. Accordingly,unlike the conventional blood inspecting apparatus, it is not necessaryto separately provide a piping and a nozzle interconnecting the flowrate sensor 52 and the blood filter 2 from the pipings 74, and 76through 79 of the liquid discharging mechanism 5 and the liquiddischarging nozzle 50. As a result, the blood inspecting apparatus 1 canhave a apparatus configuration simplified, and can be manufactured withan advantage in cost, and can be miniaturized. Moreover, because thenumber of nozzles and the valves subjected to drive control is reduced,the mean-time-between-failure (MTBF) can be extended. Furthermore,because the flow rate sensor 52 is provided at the halfway of the pipingof the liquid discharging mechanism 5, it is not necessary to separatelyprovide a piping for the flow rate sensor 52 from the pipings 74, and 76through 79 of the liquid discharging mechanism 5, and the piping lengthnecessary for a blood inspection can be shortened. Accordingly, thefluid resistance at the time of a blood inspection can be reduced, sothat it becomes possible to set power necessary for actuating thepressure-reduction pump 56 at the time of a blood inspection to besmall. This results in reduction of the running cost.

The invention claimed is:
 1. A flow rate sensor adjustment method in ananalysis apparatus including a flow rate sensor for measuring a traveltime of a sample passing through a resistive body, the flow rate sensorincluding a tubular member with a straight part running straightly andat least one sensor for detecting an interface between a first fluid anda second fluid both traveling in the straight part, the straight partbeing inclined relative to a horizontal direction, the method causingthe interface to travel by what corresponds to a predetermined amount ofthe first fluid or the second fluid and adjusting a position of the atleast one sensor with respect to the traveled interface, wherein the atleast one sensor includes a plurality of sensors, a sensor located at amost upstream side or a most downstream side among the plurality ofsensors is aligned with respect to the interface, the interface isrepeatedly caused to travel by what corresponds to a predeterminedamount of the first fluid or the second fluid, and positions of theplurality of sensors other than the sensor located at the most upstreamside or the most downstream side in the plurality of sensors areadjusted every time the interface is caused to travel.
 2. The flow ratesensor adjustment method according to claim 1, wherein the inclinedangle of the straight part is adjusted after positions of the pluralityof sensors are adjusted.
 3. A flow rate sensor adjustment method in ananalysis apparatus including a flow rate sensor for measuring a traveltime of a sample passing through a resistive body, the flow rate sensorincluding a tubular member with a straight part running straightly andat least one sensor for detecting an interface between a first fluid anda second fluid both traveling in the straight part, the straight partbeing inclined relative to a horizontal direction, wherein the flow ratesensor adjustment method includes: measuring a travel time or a travelvelocity of the first fluid or the second fluid passing through areference tube by detecting the interface between the first fluid andthe second fluid with a plurality of sensors; measuring a travel time ora travel velocity of the first fluid or the second fluid passing throughthe straight part by detecting the interface between the first fluid andthe second fluid with the plurality of sensors; and adjusting respectivepositions of the plurality of sensors except a sensor located at a mostupstream side or a most downstream side among the plurality of sensorsso that the travel time or the travel velocity in the straight part isset to the travel time or the travel velocity in the reference tube.